Secondary Cancers

Risk Factors

Second 1° malignancies: Hematologic (MDS, leukemia, lymphoma)

Alkylating chemotherapy (latency 5-7 y, chromosomal abnormalities: Del 5, 7)

Topoisomerase II inhibitors (latency 1-3 y); RT exposure

Second 1° malignancies: Solid tumors

Irradiation of solid organs (NEJM 2003;349:640)

1) Breast CA w/RT in women <35 y

2) Angiosarcoma of breast w/prior breast CA RT (rare)

3) Lung CA w/RT, ↑ w/tobacco use

4) Colon CA w/RT to abdomen

5) Thyroid CA w/RT

Head & neck CA pts w/tobacco use hx have 3-7% risk/y of second 1° CA

Complications by Organs

Risk Factors

CV disease

CMP

Atherosclerosis

Anthracyclines (cumulative dose-dependent >300 mg/m², ↑ risk w/concurrent RT & younger age at tx) (NEJM 1998;24:900)

Trastuzumab

Cisplatin (seen in young ♂ treated for testicular CA), RT-related CAD

No clear guidelines on screening for heart disease after treatment

GI

Dysmotility, malabsorption

Hepatic dysfunction

RT, surgery (gastrectomy), Vinca drugs

MTX, carmustine

Impaired immune function

Steroids, rituximab, alemtuzumab, stem cell transplant, splenectomy

Lymphatic

Lymphedema

RT, LN dissection

Musculoskeletal

Bone & soft tissue damage

Osteonecrosis

Prolonged steroid use (leading to AVN)

GnRH agonists (prostate CA)

Aromatase inhibitors (breast CA)

Neck drop w/RT

Skin induration/fibrosis (RT, chronic GVHD)

Bisphosphonates

Neurologic

Cognitive changes, fatigue

Neuropathy

WBRT; chemotherapy, hormonal agents

Cisplatin, Vinca alkaloids

Pulm complications:

Pneumonitis, BOOP

Chemotherapy lung tox

Long-term respiratory sxs

Radiation-induced changes

Bleomycin, Taxanes, Gemcitabine, TKIs, Trastuzumab

Surgical resection, ↓ PFTs

Renal

Impaired kidney function

Cisplatin, MTX, nitrosoureas, RT

Reproductive organs

Infertility & sexual dysfunction

Ovarian failure, premature menopause, or azoospermia 2° chemotherapy

SERMs, aromatase inhibitors; GnRH agonists, antiandrogens

Pelvic radiation, nerve injury s/p surgery

Thyroid pb

Hypothyroidism

Thyroid nodules

Neck radiation (dose-dependent)

RT exposure, dose >20-30 Gy